Systematic relationship of parapatric tree squirrel species (Tamiasciurus) in the Pacific Northwest

1982 ◽  
Vol 60 (9) ◽  
pp. 2149-2156 ◽  
Author(s):  
Stephen L. Lindsay
Keyword(s):  
Pacific Northwest ◽  
Taxonomic Distance ◽  
The Pacific ◽  
Tree Squirrels ◽  
History Of ◽  
Tree Squirrel ◽  
Components Analysis ◽  
Relationship Of ◽  
Two Populations ◽  
Pelage Coloration

Phenetic analysis of 20 cranial characters was used in an evaluation of the systematics of two Pacific Northwest tree squirrels, Tamiasciurus douglasii and T. hudsonicus. Although these species are predominantly allopatric, there exist at least three zones of sympatry along a parapatric border in British Columbia, Washington, and Oregon. Two populations of supposedly hybrid squirrels have been described, and these were evaluated in relation to allopatric populations of both species from throughout the area. Principal components analysis, clustering of taxonomic distance coefficients, and discriminant analysis showed a strong morphologic distinctness between the two species. These analyses also consistently placed "hybrid" specimens with one species or the other and gave no indication of intergradation. The Pleistocene glacial history of the Pacific Northwest is used to explain the divergence of the two species as well as the formation of the parapatric species border. In addition, postglacial character convergence in pelage coloration and squirrel size in forest areas allowing noncompetitive coexistence is used to explain the apparent hybrids and to account for the disjunct Vancouver Island distribution of T. douglasii-like T. hudsonicus. It is concluded that with the lack of hybridization and the presence of character convergence in zones of sympatry, reproductive isolation between T. douglasii and T. hudsonicus is complete.

Canopy disturbances over the five-century lifetime of an old-growth Douglas-fir stand in the Pacific Northwest

2002 ◽  
Vol 32 (6) ◽  
pp. 1057-1070 ◽  
Author(s):  
Linda E Winter ◽  
Linda B Brubaker ◽  
Jerry F Franklin ◽  
Eric A Miller ◽  
Donald Q DeWitt
Keyword(s):  
Pacific Northwest ◽  
Variable Density ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Old Growth ◽  
The Pacific ◽  
History Of ◽  
Horizontal Heterogeneity ◽  
Restoration Strategies

The history of canopy disturbances over the lifetime of an old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand in the western Cascade Range of southern Washington was reconstructed using tree-ring records of cross-dated samples from a 3.3-ha mapped plot. The reconstruction detected pulses in which many western hemlock (Tsuga heterophylla (Raf.) Sarg.) synchronously experienced abrupt and sustained increases in ringwidth, i.e., "growth-increases", and focused on medium-sized or larger ([Formula: see text]0.8 ha) events. The results show that the stand experienced at least three canopy disturbances that each thinned, but did not clear, the canopy over areas [Formula: see text]0.8 ha, occurring approximately in the late 1500s, the 1760s, and the 1930s. None of these promoted regeneration of the shade-intolerant Douglas-fir, all of which established 1500–1521. The disturbances may have promoted regeneration of western hemlock, but their strongest effect on tree dynamics was to elicit western hemlock growth-increases. Canopy disturbances are known to create patchiness, or horizontal heterogeneity, an important characteristic of old-growth forests. This reconstructed history provides one model for restoration strategies to create horizontal heterogeneity in young Douglas-fir stands, for example, by suggesting sizes of areas to thin in variable-density thinnings.

scholarly journals INVESTIGATING THE EVOLUTIONARY HISTORY OF THE PACIFIC NORTHWEST MESIC FOREST ECOSYSTEM: HYPOTHESIS TESTING WITHIN A COMPARATIVE PHYLOGEOGRAPHIC FRAMEWORK

Evolution ◽  
2005 ◽  
Vol 59 (8) ◽  
pp. 1639-1652 ◽  
Author(s):  
Brayan C. Cartens ◽  
Steven J. Brunsfeld ◽  
John R. Demboski ◽  
Jeffrey M. Good ◽  
Jack Sullivan
Keyword(s):  
Hypothesis Testing ◽  
Pacific Northwest ◽  
Forest Ecosystem ◽  
Evolutionary History ◽  
Mesic Forest ◽  
The Pacific ◽  
History Of

Surf Writers of the Resolution and Discovery: Texts, Waves, Politics, and Death at Kealakekua Bay

2020 ◽  
Vol 44 (1) ◽  
pp. 1-26
Author(s):  
Lance Bertelsen
Keyword(s):  
Pacific Ocean ◽  
Journal Entry ◽  
The Third ◽  
The Sublime ◽  
The Pacific ◽  
Official History ◽  
History Of ◽  
The Pacific Ocean ◽  
Relationship Of ◽  
First Descriptions

The first descriptions of Hawaiian surfing were written by David Samwell, surgeon of HMS Discovery, and James King, second lieutenant of HMS Resolution, in the months bracketing Captain James Cook’s death at Kealakekua Bay on 14 February 1779. In his journal entry for 22 January, Samwell described Hawaiians surfing six- to seven-foot “alaias” on the “great swell rolling into the Bay,” and in March 1779, King recorded his version of the same event, but neither text was published until 1967. In 1784, King published a significantly revised and expanded version of the scene in the third volume of the official history, A Voyage to the Pacific Ocean. This skewed chronology has led to some disorientation among historians of surfing, while historians of Cook’s voyages, for the most part, have neglected the surfing episodes altogether. In this essay, I address the descriptions in four interrelated contexts: (1) the history of the texts themselves; (2) their importance to the history of surfing; (3) the significance of the swell occurring during the Makahiki festival; and (4) the emotional and metaphorical impact of the scene on Western observers/writers schooled in the politics of the sublime. In the final two contexts, I suggest the metaphorical and material relationship of the scenes to King’s famous description of Cook’s death in A Voyage to the Pacific Ocean and to Samwell’s equally famous response in A Narrative of the Death of Captain Cook (1786).

Embracing the East: White Women and American Orientalism. By Mari Yoshihara. New York: Oxford University Press, 2003; pp. 242. $55 cloth, $19.95 paper; Cold War Orientalism: Asia in the Middlebrow Imagination, 1945–1961. By Christina Klein. Berkeley: University of California Press, 2003; pp. 316. 55 cloth, $21.95 paper.

2004 ◽  
Vol 45 (2) ◽  
pp. 279-282
Author(s):  
Josephine Lee
Keyword(s):  
New York ◽  
Cold War ◽  
Asian Americans ◽  
White Women ◽  
The United States ◽  
Yellow Peril ◽  
American Orientalism ◽  
The Pacific ◽  
History Of ◽  
Relationship Of

Since Edward Said's influential formulation, scholars in a variety of disciplines have unpacked orientalism in its various incarnations. Within American studies, theories of orientalism have been used to understand more fully both the relationship of the United States to Asia during the “Pacific century” and the history of racial formation and racism with regard to Asian Americans. One of the prevailing tendencies has been to posit the Oriental as that which is marginalized and excluded, as either the exotic Other or the yellow peril. Both Mari Yoshihara's Embracing the East and Christina Klein's Cold War Orientalism do much to refocus this discussion, using contexts that demonstrate how Asia and Asian Americans were not just treated as, to use Alexander Saxton's phrase, “the indispensable enemy,” but rather held, both politically and culturally, within a much more paradoxical “embrace.”

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